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Published on: May 29, 2018
Light-induced chaotic rotations in nematic liquid crystals
1Laboratoire de Physique UMR 5672, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon Cedex 07, France.
Summary
Nonlinear rotation regimes in liquid crystals exhibit a transition to chaos. This complex dynamics, driven by light intensity, is explained by transverse nonlocal effects and a coupled rotator model.
Area of Science:
- Optics and Photonics
- Soft Matter Physics
- Nonlinear Dynamics
Background:
- Nematic liquid crystals exhibit complex behaviors when subjected to optical excitation.
- Understanding nonlinear phenomena in liquid crystals is crucial for developing advanced optical devices.
- Boundary conditions invariant by rotation were applied to the liquid-crystal film.
Purpose of the Study:
- To investigate the nonlinear rotation regimes in optically excited nematic liquid crystals.
- To identify the transition to chaos and its underlying mechanisms.
- To develop a model explaining the observed dynamics.
Main Methods:
- Optical excitation with circularly polarized light.
- Circularly symmetric intensity profile with a small beam diameter.
- Observation of nonlinear rotation regimes and transition to chaos via quasiperiodicity.
- Development of a coupled rotator model for qualitative explanation.
Main Results:
- Various nonlinear rotation regimes were observed.
- A transition to chaos via quasiperiodicity was identified by increasing light intensity.
- Transverse nonlocal effects were suggested as the cause of the observed dynamics.
Conclusions:
- The study reveals complex nonlinear dynamics in liquid crystals under specific optical conditions.
- Transverse nonlocal effects play a significant role in the observed chaotic transitions.
- A simple coupled rotator model provides a qualitative understanding of the liquid-crystal dynamics.
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